The slideshow is not showing new photos — why?

Usually approval is switched on, the photos are private, or the screen’s browser lost its connection — reloading the page restores it.

Three causes, in the order they are worth checking:

1. Require approval is on. Nothing reaches the slideshow until you publish it. Check the moderation queue.
2. The photos are private. A guest who turned off “Make photo public”, or a photo you hid, will never be on the screen. This is working correctly. (A gallery set to private still shows its photos on your screen — the setting decides who can open the gallery, not which photos are in it.)
3. The screen’s browser lost its connection. The slideshow holds an open connection to receive new photos; a laptop that slept, or venue WiFi that dropped, breaks it. Reload the page.

If photos are appearing in the gallery but not on the screen, it is the third one.